1. Field
The present invention relates to an image enlarging apparatus and method.
2. Related Art
Televisions or displays with a large number of pixels, i.e., with a high resolution have come into widespread use. When the televisions or displays each display an image, they convert the number of pixels of the image data into the number of pixels of the panel. For performing a high resolution processing, there is known an interpolation method (such as a cubic convolution method or a BiCubic method) in which a filtering processing is carried out with a Sinc function based on the sampling theorem, or a multiframe degradation inverse transformation method which can provide a sharper image than this (see, e.g., JP-A-2000-188680 (kokai), or S. Park, et. al., Super-Resolution Image Reconstruction: A Technical Overview, IEEE Signal Processing Magazine, USA, IEEE, May 2003, p. 21 to 36).
The multiframe inverse transformation method is the following high-resolution processing method. Noticing the fact that the subject imaged in a reference frame (a frame to be increased in resolution) is also imaged in another frame continuous thereto, the motion of the subject is detected with decimal accuracy of equal to or less than the pixel interval. Then, a plurality of sample values shifted microscopically in position with respect to the same local portion of the subject are determined. Thus, the pixel values are sequentially corrected using an interpolation method one for each of a plurality of the sample values.
With a conventional multiframe degradation inverse transformation method, the pixel values are corrected sequentially for each of a plurality of the sample values. Therefore, the correction processing is time consuming, so that unfavorably the high resolution processing cannot be carried out at a high speed.